In Europa Universalis IV, you can't wage war and expand all the time. There are a number of game mechanics that will stop you: Unrest in the provinces you took, overextension, other countries counting your "aggressive expansion" score, war exhaustion, manpower depletion, etc. Thus a normal game of Europa Universalis IV is dominated by a cycle: Wage war when the opportunity is rife, take some provinces, and then spend some years to integrate the new provinces, and calm down your population and the neighbors, until you wage the next war. Playing as non-expansive Switzerland, I only had to wage war early to grow into the later historical borders, and the mission tree for Switzerland gives bonuses that avoids most of the expansion problems you'd otherwise have. And then, in "only" 40 hours, I could play at relatively high speed through nearly 4 centuries of history. I learned a lot about playing "tall", finished most of the mission tree of Switzerland, and had quite a successful game. It was fun. And it got me to the point where I am thinking that I won't be playing Europa Universalis IV again.

A decade ago or so, I made a tragic mistake: I considered Europa Universalis IV to be too complicated, and never played it until now. Instead I tried other Paradox grand strategy games, didn't like Hearts of Iron IV, but played a good amount of Victoria 3 and Crusader Kings III. In hindsight, I actually like Europa Universalis IV better than Vic3 or CK3. While EU4 certainly has problems with accessibility, it turns out that the stronger focus of the other games (economy in Vic3, characters in CK3) is actually less fun than the all-encompassing EU4. Europa Universalis IV is also a lot "easier", as in the player having a higher chance to succeed and grow into a large empire, even if he doesn't understand all the details. I had several games in Victoria 3 where my economy somewhat unexpectedly went south, or my kingdom in Crusader Kings 3 split up into several parts just because I had had too many children randomly. In Europa Universalis IV the details are often confusing, but I usually had a good grasp of what was going on, and what to do to succeed.

But Europa Universalis V is on the horizon, so with the UI and quality-of-life features of EU4 being distinctly lacking, there not being any more patches or content additions, and EU4 requiring a subscription to use all DLCs, I will most probably play the sequel EU5, and never look back to EU4.

The only weird thing about the transition from EU4 to EU5 will probably be that much of what I have learned in EU4 isn't applicable in EU5. A lot of playing Europa Universalis IV is not about grand strategy considerations, but dealing with very detailed and very specific rules. When playing as Portugal I learned that for example the game handles a colony in South America very differently from a colony in Africa. There are fewer universal rules, and more local rules, than in other grand strategy games. With the engine of EU5 being much different, I suspect that all those specific rules will be different, and I'll have to learn them all over again.